AniDB wrote:"Sometimes the sun is a gentle mother, bringing life to the surface of the Earth. And sometimes a strict father, who brings trials. These trials, which have happened many times since the creation of Earth, have come again. The land is dry, the oceans vanished. And vast seas of sand were born. Most of the life that survives is in danger of extinction, clinging to the thin atmosphere that remains. But some still live on, seeking out a tiny glimpse of hope... in the dry seas of sand." — from the intro

Sam Coin witnesses how a young women named Maya is relentlessly pursued by several Theseus Sand-borne Destroyers when an Ozma, a gigantic sand whale, surfaces cutting them off. Sam only barely saves Maya from being buried by sand, and the Theseus army, believing her to have died in the incident, seems to give up the search...

Sam brings Maya to Port Oase, a still thriving independent town, placed in a rock canyon. Neither Mimei a good friend nor Captain Binas are thrilled by the sudden appearance of mysterious Maya... and when the Theseus army shows up, the chase for the sand pirate ship, Bardanos, with Maya on board is on.